Improvement in machines for cutting and forming sheet-metal fence-barbs



E & A. CHILDREN. Machine for Cutting and Forming Sheet-MetalFence-Barbs.

Patent 'ed Feb J1. 1879.

ma-ens, Pnom-umoamPHER.W D c 3 Sheets-Sheet 1.

UNITED STATES Furor:

PATENT IMPROVEMENT IN MACHINES FOR CUTTING AND FORMING SHEET-METALFENCE-BARBS.

Specification forming part of Letters Patent No. 212,091, dated February11, 1879; application filed April 30, 1878.

To all whom it may concern:

Be it known that we, EDwIN CHILDREN and ARTHUR G. CHILDREN, of Dunleith,Jo Daviess county, State of Illinois, have invented certain Improvementsin Machines for Outting and Forming Sheet-Metal Fence-Barbs, of whichthe following is a specification:

The nature of the invention will be understood from the followingdescription of the construction and operation of the machine shown inthe drawings.

Figure 1 of the said drawings is a perspective view of the machine, andalso of one of the completed barbs. Fig. 2 is a top or plan view of themachine, Fig. 3 is a perspective diagram of the principal shaft and itscams. Fig. 4 is a fragmentary plan view of the feed, cutting-die, andpresser'foot. Fig. 5 is a sectional view of the machine on the line a: 3of Fig. 4. Fig. 6 shows three detail views of the cutting and formingdies.

Like letters of reference wherever used throughout all the figuresdenote like parts.

The style of barb which my machine is adapted to make is what is knownas the Frcntress four-point sheet-metal barb. Diamond-shaped blanks, cutdiagonally from a flat bar or band of sheet metal, are slit at the acuteangles, as shown at Fig. 5, A, and the slit parts bent in oppositedirections, forming the completed barb like that shown at Fig. 1, A.

The first operation of the machine, taking the natural order, is thefeeding of the strip of sheet metal to the dies, which is accomplishedby the mechanism now to be described, in such manner that the length ofa single barb, counting such length as the distance from one of theacute angles to one of the obtuse angles, is fed at each operation, andan operation is completed at each revolution of the main shaft B.

Upon said shaft B is a pair of cams, C O. The cam G imparts areciprocating motion to the slide D, which is connected by an arm, D, toa rock-shaft, D having another arm, D connected to the slidingreciprocal carriage 1), upon which is borne the strip of sheet metal tobe fed to the dies. The strip lying upon the carriage passes under astationary plate,D below which is a gri pin g-cam, I), that clamps thestrip from beneath up against the plate lightly at all times, exceptwhen the carriage is moving back from the dies. This griping-cam' isoperated by the connections I) from the eccentric 0, above mentioned asone of a pair upon the main shaft B. The result of this mechanism isthat the strip clamped by the griper is fed forward the distance thatthe carriage moves, and being seized in front by a severing knife ordie, presently to be described, is there held while the carriage returnsto take a fresh hold. In order that there may be no break in the feed,and no dropping or displacement of the strip as it is being used up, Ilead the strip from the griping-cam and carriage to the dies between apair of guidebars, D one above and one below the strip.

The strip is led by the guide-bars into a horizontal slot which passesthrough a vertically-moving head, E. Thelower lip of this slot, at theside nearest the dies, is provided with a cutting-edge, E, which isopposedto a stationary cutting-edge, E upon the frame of the machine. Apair of cams, E E give an up-and-down movement to the head E from theshaft B by connections E. This movement is so timed that the knife orcutting edge E in the sliding head rises and severs the strip diagonallyjust as the feed-carriage has finished its backward movement, and justbefore the strip is fed forward. The diamondshaped blank thus cut offfrom the strip is pushed forward beneath a spring presser-foot, F, bythe strip being fed after it, until it comes into position to be actedupon by the slitting and forming dies in advance.

The slitting and forming of the blank are done at a single operation bytwo pairs of dies operating in different directions. Each pair of diesconsists of a stationary and a moving die. The stationary dies G G aresecured to the frame of the machine, the upper one, G

having'its cutting-edge below, and the lower one, Gr, its cutting-edgeabove. The moving dies g g oppose the stationary dies, and are carriedin a shell, H, which makes a partial rotation. The stationary and movingdies are thus opposed to each other to act with a shearing cut, so thatwhen the blank is in place and the shell Hrotatedin such manner as tocarry the die g upward and the die 9 downward, their action inconjunction with the stationary dies will be to slit the diamond-shapedblank at the acute angle at each end. The forming action of these dies,although difficult to describe, will be readily understood by any oneconversant with the art of cutting sheet metal with shears, the tendencyof the blades, as they pass in making the out, being to carry the metalupon one side of the cut in one direction and upon the other side in theother direction,producing the curve of the metal, as it is called. Inshort, the moving blade g carries with it half of the slit angle of thediamond at one end in its upward course, andg carries the same half atthe other end in its downward course; and as the other side of the blankis not tightly clamped, but lies in a cavity, G the bend divides itselfbetween the two halves of the two acute angles and produces thesymmetrical barb. The amount of bend may be made to vary as the motionof the dies is changed, or as they are ground or set.

The required reciprocating motion of the dies is produced as follows: Acrank, J, upon the shaft B is connected by a pitman, J, to a wrist-pinupon the quadrant K, which is connected by a pitman, J from anotherwrist-pin to the rotary shell H. We have described everything about thisrotary holder or shell H which is necessary to its successful operation.Difl'erence is made between the distance from the centers of thequadrant and crank to cause the well-known reverse or swing action,which produces the required reversal of the shell, while thedead-centers produce the required pauses. As fast as the barbs areformed and the knives reverse they are discharged from the machine bythe feeding forward of the succeeding blank.

YVe claim- 1. The combination of the feed, the cuttingdies which severthe blank from the bar or strip, and the shearing-diesfor slitting andforming the barb, the latter located in advance of the severing-dies, sothat thefeed of the bar crowds forward the severed blanks to position inthe shears, substantially as specified.

2. The pair of shearing-dies, the moving blades of which move inopposite directions, in combination with a mechanism for holding andguiding the severed blank thereto, substantially as specified.

3. The dies for sllitting and forming the barb, in combination with acavity in which the barb lies loosely while being sheared and formed,substantially as specified, to permit the bend of the points to divideitself between the two halves of the blank.

4. The combination, with the forming-dies and the severing-dies, of thefeed-carriage, griping-cam, guide-bars, and the mechanism for operatingthe same, in the manner and with the timing specified.

5. The combination of the shaft B, cams G C, slide D, arm D, rock-shaftD arm D3, carriage D plate D griping-cam D guidebars D moving head E,cutting-edge E, cuttingedge E cams E E connections E presser-foot F,dies G G g g, shell H, crank J, pitman J quadrant K, and pitinan Jsubstantially as specified.

ED'WIN CHILDREN. ARTHUR G. CHILDREN. Vitnesses:

JAMES GARNIGK, H. ALLMAN.

